894 research outputs found

    Limits on the low energy antinucleon-nucleus annihilations from the Heisenberg principle

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    We show that the quantum uncertainty principle puts some limits on the effectiveness of the antinucleon-nucleus annihilation at very low energies. This is caused by the fact that the realization a very effective short-distance reaction process implies information on the relative distance of the reacting particles. Some quantitative predictions are possible on this ground, including the approximate A-independence of antinucleon-nucleus annihilation rates.Comment: 10 pages, no figure

    Echocardiographic screening in pediatric asymptomatic or paucisymptomatic coronavirus disease 2019 outpatients: Is it a useful test or an excess of zeal?

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    IntroductionData regarding echocardiographic findings during follow-up of asymptomatic or pauci-symptomatic coronavirus disease 2019 (COVID-19) are scarce in pediatric patients. The aim of the present study is to assess post-COVID-19 sequelae through echocardiography in children who have experienced mild SARS-CoV-2.MethodsThis single-center, retrospective, observational study enrolled a cohort of 133 pediatric outpatients, born between 2005 and 2022, with a history of asymptomatic or paucisymptomatic SARS-CoV-2 infection, who underwent transthoracic echocardiographic (TTE) evaluation at an outpatient pediatric clinic in Northern Italy.ResultsThe percentage of the pediatric activity of the clinic which was focused on post-COVID evaluation was not negligible, representing almost 10% of the similar to 1500 pediatric patients examined from 1 January 2021 to 31 August 2022. According to ACEP classification, children enrolled in this study had previously experienced in 72.9% (97) asymptomatic COVID-19 and nearly 27% (36) a mild illness. Clinical and instrumental examinations did not show any relevant abnormality in the functional [left ventricular ejection fraction (LVEF), tricuspid annular plane systolic excursion (TAPSE), pulmonary artery systolic pressure (PASP)] or structural [interventricular septum diameter (IVSd), left ventricular internal diameter (LViD, end-diastolic volume (EDV), left atrium volume (LAV)] parameters examined related to SARS-CoV-2 infection in the total of 133 children.ConclusionAccording to our results, children who experienced an asymptomatic or mild SARS-CoV-2 infection should not be systematically investigated with second-level techniques, such as TTE, in the absence of clinical suspicion or other risk conditions such as congenital heart diseases, comorbidities or risk factors

    A development cooperation Erasmus Mundus partnership for capacity building in earthquake mitigation science and higher education

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    Successful practices have shown that a community’s capacity to manage and reduce its seismic risk relies on capitalization on policies, on technology and research results. An important role is played by education, than contribute to strengthening technical curricula of future practitioners and researchers through university and higher education programs. EUNICE is a European Commission funded higher education partnership for international development cooperation with the objective to build capacity of individuals who will operate at institutions located in seismic prone Asian Countries. The project involves five European Universities, eight Asian universities and four associations and NGOs active in advanced research on seismic mitigation, disaster risk management and international development. The project consists of a comprehensive mobility scheme open to nationals from Afghanistan, Bangladesh, China, Nepal, Pakistan, Thailand, Bhutan, India, Indonesia, Malaysia, Maldives, North Korea, Philippines, and Sri Lanka who plan to enroll in school or conduct research at one of five European partner universities in Italy, Greece and Portugal. During the 2010-14 time span a total number of 104 mobilities are being involved in scientific activities at the undergraduate, masters, PhD, postdoctoral and academic-staff exchange levels. Researchers, future policymakers and practitioners build up their curricula over a range of disciplines in the fields of earthquake engineering, seismology, disaster risk management and urban planning

    EU-NICE, Eurasian University Network for International Cooperation in Earthquakes

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    Despite the remarkable scientific advancements of earthquake engineering and seismology in many countries, seismic risk is still growing at a high rate in the world’s most vulnerable communities. Successful practices have shown that a community’s capacity to manage and reduce its seismic risk relies on capitalization on policies, on technology and research results. An important role is played by education, than contribute to strengthening technical curricula of future practitioners and researchers through university and higher education programmes. In recent years an increasing number of initiatives have been launched in this field at the international and global cooperation level. Cooperative international academic research and training is key to reducing the gap between advanced and more vulnerable regions. EU-NICE is a European Commission funded higher education partnership for international development cooperation with the objective to build capacity of individuals who will operate at institutions located in seismic prone Asian Countries. The project involves five European Universities, eight Asian universities and four associations and NGOs active in advanced research on seismic mitigation, disaster risk management and international development. The project consists of a comprehensive mobility scheme open to nationals from Afghanistan, Bangladesh, China, Nepal, Pakistan, Thailand, Bhutan, India, Indonesia, Malaysia, Maldives, North Korea, Philippines, and Sri Lanka who plan to enrol in school or conduct research at one of five European partner universities in Italy, Greece and Portugal. During the 2010-14 time span a total number of 104 mobilities are being involved in scientific activities at the undergraduate, masters, PhD, postdoctoral and academic-staff exchange levels. This high number of mobilities and activities is selected and designed so as to produce an overall increase of knowledge that can result in an impact on earthquake mitigation. Researchers, future policymakers and practitioners build up their curricula over a range of disciplines in the fields of engineering, seismology, disaster risk management and urban planning. Specific educational and research activities focus on earthquake risk mitigation related topics such as: anti-seismic structural design, structural engineering, advanced computer structural collapse analysis, seismology, experimental laboratory studies, international and development issues in disaster risk management, social-economical impact studies, international relations and conflict resolution

    Combined bezafibrate and medroxyprogesterone acetate: potential novel therapy for acute myeloid leukaemia

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    Background: The majority of acute myeloid leukaemia (AML) patients are over sixty years of age. With current treatment regimens, survival rates amongst these, and also those younger patients who relapse, remain dismal and novel therapies are urgently required. In particular, therapies that have anti-leukaemic activity but that, unlike conventional chemotherapy, do not impair normal haemopoiesis. Principal Findings: Here we demonstrate the potent anti-leukaemic activity of the combination of the lipid-regulating drug bezafibrate (BEZ) and the sex hormone medroxyprogesterone acetate (MPA) against AML cell lines and primary AML cells. The combined activity of BEZ and MPA (B/M) converged upon the increased synthesis and reduced metabolism of prostaglandin D2 (PGD2) resulting in elevated levels of the downstream highly bioactive, anti-neoplastic prostaglandin 15-deoxy Δ12,14 PGJ2 (15d-PGJ2). BEZ increased PGD2 synthesis via the generation of reactive oxygen species (ROS) and activation of the lipid peroxidation pathway. MPA directed prostaglandin synthesis towards 15d-PGJ2 by inhibiting the PGD2 11β -ketoreductase activity of the aldo-keto reductase AKR1C3, which metabolises PGD2 to 9α11β-PGF2α. B/M treatment resulted in growth arrest, apoptosis and cell differentiation in both AML cell lines and primary AML cells and these actions were recapitulated by treatment with 15d-PGJ2. Importantly, the actions of B/M had little effect on the survival of normal adult myeloid progenitors. Significance: Collectively our data demonstrate that B/M treatment of AML cells elevated ROS and delivered the anti-neoplastic actions of 15d-PGJ2. These observations provide the mechanistic rationale for the redeployment of B/M in elderly and relapsed AML

    Trait Aggressiveness Predicting Aggressive Behavior: The Moderating Role of Meta-Cognitive Certainty.

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    Research on aggression has benefitted from using individual-difference measures to predict aggressive behavior. Research on meta-cognition has recently identified that the predictive utility of individual-difference inventories can be improved by considering the certainty with which people hold their self-views. Merging these two frameworks, the present research examines whether assessing certainty in trait aggressiveness improves its ability to predict aggressive outcomes. Across two studies, participants reported their level of trait physical aggressiveness and the certainty with which they held their responses to the scale (predictor variables). Aggressive behavioral intentions (Study 1 and 2) and actual aggressive behavior (Study 2) were used as dependent measures. As hypothesized, results indicated that certainty moderated the effects of individual-differences in aggressiveness on both aggressive outcomes. Therefore, considering the certainty with which people hold their relevant traits can be useful for understanding aggression, and also for predicting the consistency between personality and behavior.pre-print741 K

    Three Dimensional Annihilation Imaging of Antiprotons in a Penning Trap

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    We demonstrate three-dimensional annihilation imaging of antiprotons trapped in a Penning trap. Exploiting unusual feature of antiparticles, we investigate a previously unexplored regime in particle transport; the proximity of the trap wall. Particle loss on the wall, the final step of radial transport, is observed to be highly non-uniform, both radially and azimuthally. These observations have considerable implications for the production and detection of antihydrogen atoms.Comment: Invited Talk at NNP03, Workshop on Non-Neutral Plasmas, 200

    Stability of the nonlinear dynamics of an optically injected VCSEL

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    Automated protocols have been developed to characterize time series data in terms of stability. These techniques are applied to the output power time series of an optically injected vertical cavity surface emitting laser (VCSEL) subject to varying injection strength and optical frequency detuning between master and slave lasers. Dynamic maps, generated from high resolution, computer controlled experiments, identify regions of dynamic instability in the parameter space. © 2012 Optical Society of America

    Positron plasma diagnostics and temperature control for antihydrogen production

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    Production of antihydrogen atoms by mixing antiprotons with a cold, confined, positron plasma depends critically on parameters such as the plasma density and temperature. We discuss non-destructive measurements, based on a novel, real-time analysis of excited, low-order plasma modes, that provide comprehensive characterization of the positron plasma in the ATHENA antihydrogen apparatus. The plasma length, radius, density, and total particle number are obtained. Measurement and control of plasma temperature variations, and the application to antihydrogen production experiments are discussed.Comment: 5 pages, 4 figures, to be published in Phys. Rev. Let
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